Vegetation of the tundra and forest tundra

The vegetation of the tundra and forest-tundra, its forms, methods of plant multiplication, adaptability to survival largely depend on the characteristics that characterize these zones.

Geographical position

The location of the tundra zone lies on the subarctic belt of the Earth. On the continent of Eurasia, it stretches along the entire coast of the seas of the Arctic Ocean for tens of thousands of kilometers. North coast of the mainland North America, too, is occupied by the tundra. The length of the zone from north to south is on average about 500 kilometers. In addition, the tundra occupies some islands near Antarctica. In the mountains, where high altitude zones are expressed, mountain tundra is formed. Considering all the territories where the zone is located, its total area on the planet has been calculated. It is about 3 million km2.

Lesotundra is a zone where tundra vegetation and taiga vegetation are located in small areas. Lesotundra stretches from west to east to the south of the tundra on the continents of Eurasia and North America. The length of the strip from north to south varies in the range from 30 to 400 kilometers. On the southern borders, the forest-tundra passes into the forest zone.

Climatic conditions affecting the growth of plants

The climate of the tundra zone and forest-tundra is very severe. The duration of the winter is from 6 to 8 months a year. During all this time, a constant snow cover keeps, the air temperature sometimes drops to 50 degrees below zero. The polar night lasts about two months. Hard cold winds, snow storms almost never abate.

Summer in the tundra is short and cool. Possible frost and precipitation in the form of snow. Despite the polar day, the surface of the earth does not receive much heat, as the sun does not rise high above the horizon and sends scattered rays to Earth. To survive in such conditions, the vegetation of the tundra must adapt.

The influence of permafrost on the species composition of vegetation

In the warm season in the tundra zone, the soil thaws only to a depth of not more than 50 centimeters. Then there is a layer of permafrost. This factor is one of the decisive factors in the resettlement of plants in the tundra zone. The same factor affects their species diversity.

Permafrost has a significant impact on the terrain. Freezing and thawing of rocks leads to their deformation. As a result of the punching process, surface forms such as hillocks appear. Their height is no more than two meters above sea level, but the appearance of such forms also affects the vegetation of the tundra, its settlement over a certain territory.

Effect of soil on species diversity of vegetation

In the zone of the tundra and forest-tundra there is a high waterlogging of soils. It is especially noticeable during the melting of snow. Water can not penetrate deep into the air due to the presence of permafrost. Its evaporation also does not have a high intensity due to the low temperature of the air. For these reasons, melt water and precipitated deposits accumulate on the surface, forming large and small bogs.

High waterlogging, the presence of permafrost, the predominance of low temperatures hamper the flow of chemical and biological processes in the soil. It contains little humus, accumulates ferrous oxide. Tundra-gley soils are suitable for the growth of only a few plant species. But the vegetation of the tundra also adapts to such conditions of life. A person who has been to this region during the flowering period of plants remains indelible impressions for many years - so beautiful and attractive is the flowering tundra!

In the forest-tundra the natural fertile layer of the earth is also low-powered. The soil is poor in nutrients, it is characterized by high acidity. When land is cultivated, a large number of mineral and organic fertilizers contribute to the composition of the soil. On the cultivated areas of the forest-tundra, there are more diverse herbaceous vegetation, trees and shrubs.

Types

The vegetation of the tundra and forest-tundra largely depends on the type of natural zones. Their landscapes only at first glance seem monotonous.

Kochkarnaya and bumpy tundra occupy the largest territories. Among the marshes, the plant turf forms hillocks and bumps, on which many plant species take root. A special type of tundra is polygonal. Here you can observe the shape of the relief in the form of large polygons, which are broken by depressions and frost cracks.

There are other approaches to the classification of such a natural zone as the tundra. What vegetation prevails in a certain territory, such is the type of tundra. For example, moss-lichen tundra consists of areas covered with different types of mosses and lichens. There are also shrub tundra, where thickets of polar willow, cedar elfin, bushy alder are common.

Plants

As stated earlier, the vegetation of the tundra and forest-tundra should have adapted to the harsh climatic conditions of the subarctic belt of the Earth. Otherwise, her life and development would not be possible here.

The adaptability of tundra and forest-tundra plants is as follows. Most fauna representatives are perennials. Annuals with a short duration of summer could not complete their life cycle. Only a small part of the plants multiplies by seeds. The main way of prolonging life is vegetative.

The low growth of tundra plants allows them to withstand during strong winds. This is also facilitated by the creeping nature of the shoots and their ability to intertwine, forming a sort of soft pillow. In winter, all parts of plants are under snow. This saves them from severe frosts. Most of the tundra and forest tundra plants have a waxy coating on the leaves, which contributes to the moderate evaporation of moisture from their surface.

Vegetation of the tundra, photographs of some species of which are in the article, are represented by long-term frost-resistant grasses: sedge, which prevails in lowlands and marshes, buttercup, cotton grass, dandelion, poppy. From the trees grow dwarf birch, polar willow, bushy alder. These tree species in the forest-tundra can already reach a height of three or more meters. Among the shrubs are widely distributed blueberries, cloudberries, blueberries and red bilberries. Mosses and lichens are found on the heights, many of which are the main kind of food for animals inhabiting these places.

Forest tundra and taiga

The vegetation of the tundra and taiga is very different from each other. Lesotundra is a transition zone between them. On the territory of the forest-tundra, among treeless areas, one can find islands of spruce, birch, larch and other tree species.

The zone of the forest-tundra is unique, as on its territory there is a vegetation of the tundra and vegetation of the taiga, which becomes more noticeable with the advance to the south. Areas of the forest, consisting of individual species of trees and shrubs, create the most favorable conditions for the growth of grassy vegetation. Thanks to trees and shrubs, the speed of the wind decreases, more snow is retained, which harbors plants, saving them from freezing.

Study of the vegetation of the subarctic belt

The vegetation cover of the tundra and forest-tundra has not yet been fully explored. A systematic scientific description of the species growing here began only in the middle of the last century.

To continue this work today special expeditions are being created. During these experiments, scientists are also trying to establish how the animals living in these zones influence the tundra and forest-tundra vegetation. They want to get answers to questions about whether the species diversity of plants is changing on sites protected from the presence of certain species of animals, how long it takes to completely restore the destroyed vegetation cover. So far, scientists have not found answers to all the questions concerning natural balance in the zone of the subarctic belt of the planet.

Protection of fauna

The nature of the tundra and forest-tundra is very vulnerable. On the restoration of the soil layer, vegetation cover is required not one decade, but in some cases, centuries.
Man has long realized that it is he that has a disastrous effect on the nature of the tundra and forest-tundra. Trying to atone for guilt, people created a whole range of reserves, national parks, and game reserves. They are located both in Russia and other countries of the world.